Electric hand riveting device



April 2, 1968 scHA'oucl-l ELECTRIC HAND RIVETING DEVICE 2 Sheets-Sheet 1Filed Oct. 22. 1965 INVENTOR KURT scu' loucw ATTORNEY.

April 2, 1968 K. scHAoLlci-i ELECTRIC HAND RIVE'IING DEVICE 2Sheets-Sheet 2 INVENTQR KURT SCHADLICH Filed Oct 22, 1965 ATTORNEY.

United States Patent Filed Oct. 22, 1965, Ser. No. 501,726 14 Claims.(Cl. 173-170) ABSTRACT OF THE DISCLOSURE An electric hand rivetingdevice, comprising an electric motor mounted in a housing and a gearwheel having teeth and a gap without teeth and operatively connectedwith the electric motor for turning until the gap is adjacent anoperative connection to the electric motor. A connecting rod is mountedin the housing at one end for reciprocating movement and connectedpivotally at the other end eccentrically with the gear wheel, whereupona back and forth reciprocation occurs for a single turning of the gearwheel, which gear wheel is turned by one rotation and automaticallystopped when the gap becomes adjacent the operative connection to themotor.

The present invention relates to an electric hand riveting device ingeneral and to such a device for setting and blind riveting, inparticular.

Devices are known for the setting of blind rivets which are-operated byhand pneumatically or hydraulically. Hand riveting devices are extremelydisadvantageous in a continuous operation, because the operation takesplace with a force always supplied by hand, which is extremely strenuousfor the operator. Pneumatic or pneumatic-hydraulic combined devices havethe drawback that pressurized air is not always available.

. It is, therefore, one object of the present invention to provide anelectric hand riveting device. Such device has been required for sometime for the industry operating with blind rivets. Electrical outletsare always available in contrast to connection for pressurized air.

It is another object of the present invention to provide an electrichand riveting device, wherein the drive is brought about from anelectric motor over a reduction gear onto a toothed gear, which has aninterrupted tooth arrangement, which causes the automatic standstill ofa connecting rod in a zero position which carries the feeding mechanism,and whereby the connecting rod is disposed eccentrically on the toothedgear.

The present invention permits for the first time to perform blindriveting without pressurized'air at places such as building sites,workshops and factories. The device is transportable and practically canbe operated as a cornmercially available hand bore machine. Theconstructive arrangement permits an easy operation with the device.

'With these and other objects in view which will become apparent in thefollowing detailed description, the present invention will be clearlyunderstood in connection with the accompanying drawings, in which:

FIGURE 1 is an axial section of the electric hand riveting devicedesigned in accordance with the present invention;

7 FIG. 2 is a top plan view of the device showing FIG- URE 1, thehousing being likewise shown in section; and

FIG. 3 is a section along the lines 33 of FIG. 1 of the grooved cam.

Referring now to the drawings, the electric hand riveting device, asshown in one preferred embodiment, comprises an electric motor 17 theshaft of which is con- 3,375,883 Patented Apr. 2, 1968 nectedoperatively with a reduction gear drive 16, which in turn drives a worm18 which is in mesh with a worm gear 21 mounted on a pinion shaft 22.

A pinion 11 is keyed to the pinion shaft 22 which is in mesh with theteeth of a gear 5 and one portion of the periphery of the gear 5 has agap 23 which has no teeth. Upon starting the motor 17, the latteroperates the reduction gear 16 and the worm 18, and the latter the wormgear 21, and in turn the pinion 11. When a pulling lever 13, whichextends into a slide 12, is operated, it releases by means of a pin 20-provided on the slide 12, and projecting into a grooved cam 7, the gear5. The grooved cam 7 is screwed to the axis of the gear 5. The gear 5 isbrought to rotation initially by a pulling spring 19, tensionallyconnected to the housing and eccentrically to the gear 5 through theconnecting rod 8, whereby the gap 23 in the row of teeth on the gear 5is bridged over. The pinion 11 then meshes with the teeth of the gear 5.The gear 5 makes then one revolution until again the gap 23 of teeth isdisposed opposite the pinion 11 (i.e., the zero position, referred toabove) and which releases the gear 5 from rotation. The gear 5 remainsstanding still, while the pinion 11 continues rotation. Simultaneously,the gear 5 is locked in this zero position by means of the grooved cam 7in connection with the pin 20 disposed on the slide 12.

During the rotation of the gear 5 a connecting rod 8 securedeccentrically on the gear 5 by means of a bolt 6 performs a pulling andpushing movement. The connecting rod 8 is connected with a conventionalfeeding mechanism 10 by means of a bolt 9 which is not part of thepresent invention and does not require, therefore, a detaileddescription.

During the pulling movement of the connecting rod 8 the blind rivet (notshown) is riveted. During the pushing movement the feeding mechanism isopened and the broken-off rivet pin is thrown out.

During the aboveadescribed operation of the apparatus, an electricswitch is switched-on, that means, the electric motor runs continuouslyand a. riveting operation is instituted always by operation of thepulling lever 13 and completed. This method of operation is advisableduring riveting in a continuous run.

If, for instance, blind rivets are to be set on difiiculty accessiblelocations or in horizontal planes, the switch 25 is turned-off and theblind rivet to be riveted is inserted into the mouthpiece of theapparatus. By operation of the pulling lever 13, the gear 5 is releasedby means of the pin 20 on the slide 12 and from the grooved cam 7,whereby the first tooth following the gap 23 of teeth engages one toothof the pinion 11. This slight rotary movement of the gear 5 causes acorresponding slight pulling movement of the feeding mechanism. Theclamping means (not shown) starts thereby to close at this time and inparticular to such an extent that the rivet pin of the blind rivet isgripped and is retained in this position. Upon further pushing of thelever 13 to the righthand side, a switch 15 is operated by directcontact with the lever 13; which causes the start of the electric motor.

Referring now again to the drawings and in particular to FIG. 3, thestructure of the grooved cam 7 which achieves the above operation isclearly apparentThe grooved cam 7 is provided with a first set-off slot7 defining a first abutment surface 7'a, which determines the stoppingposition during the rotary movement of the gear 5. The second set-offslot 7 defining a second abutment surface 7"a, determines the slightmovement for the clamping of the blind rivet. The abutment surfaces 7'aand 7"a face the direction of rotation of the indicated by the arrows inFIGS. 2 and 3), but the pin 20 prevents such rotation due to abutmentwith the surface 7'a, which surface 7a faces in the direction of thetendency to rotate.

However, when the lower arm of the lever 13 (FIG. 1) is depressedinwardly to the right-hand side, the pin 20 is moved by the slide 12 tothe left-hand side of slot 7, beyond and out of abutment with theabutment surface 7'a, thereby freeing the cam 7 and gear 5, andconsequently, the spring 19 can cause the gear to rotate slightlycounter-clockwise (as indicated by the arrows), with the pin slidingalong the short arcuate portion 7"" of the cam groove 7" until the pinabuts the second abutment surface 7"a in the radial set-off slot 7. Inthis position the first tooth 5a following the gap 23 (cooperativelyspaced by the gap 23 with the spacing of the cam groove portion 7"),comes into engagement with one tooth of the pinion 11, as describedabove.

Further depression of the lever 13 toward the righthand side causes thelever 13 to actuate the motor switch by direct contact therewith andalso causes the pin to move to the left-hand side (i.e., radiallyinwardly) of the slot 7 beyond and out of abutment with the secondabutment surface 7"a, whereupon the gear 5 and cam 7 is again free torotate, and now, since the pinion 11 is simultaneously actuated, andsince one tooth of the pinion 11 is in mesh with tooth 5a of the gear 5,the gear is then rotated counter-clockwise by the inion 11. During thisrotation, the pin 20 slides relatively along the eccentrically curvedcam groove 7" from slot 7" back again to the right-hand side of slot 7',during which rotation, the pin 20 moves from a radially inward position(from the inner side of slot 7") to a radially outward position (to theouter side of slot 7 thereby causing the lower arm of the lever 13 (viaslide 12) to move again to its original position, i.e., to the left-handside (FIG. 1), thereby releasing switch 15 and stopping rotation of thepinion 11, as the pin 20 reaches the slot 7'. When this position isagain reached (FIGS. l3), the pin 20 again prevents rotation of the cam7 and therefore the gear 5, against the turning force of spring 19, byabutment with the first abutment surface Ta and the beginning of the gap23 becomes positioned adjacent the pinion 11, thereby completing thecycle of a single rotation of the gear 5 and single reciprocation of theconnecting rod 8.

The pulling lever 13 is retained in the operating position of andagainst the switch 15 by means of the slide 12 in connection with thegrooved cam 7 until a complete riveting cycle has been terminated, thatis, until the gear 5 has performed a complete rotation. After thisrotation, the pulling lever 13 returns into its original position.Simultaneously, the switch 15 likewise returns into its originalposition, whereby the electric current for the drive of the electricmotor 17 is interrupted and the electric motor 17 returns to astandstill.

The driving mechanism of the apparatus is disposed in a housing 1, whilethe motor 17 is protected by a special housing 2. The mounting 26 of thegear 5 is fortified by means of a rib 3. The pinion shaft 22 is mountedin a bearing support 4 disposed above the gear 5. The pulling lever 13can be suitably spring biased by means of a spring 14, one end of whichis received in a recess 14 of the lever 13, while the other end of thespring 14 engages a support 14" which also carries the switch 15.

The present invention is not limited to the embodiment disclosed in thedrawing. It is possible, for instance, instead to use a worm gear forthe plane gear 5, which worm gear can be driven by means of a worm andwhich worm gear has likewise a tooth gap, as it is shown in connectionwith the plane gear 5. The switching means comprises cam 7, pin 20,slide 12, lever 13 and switch 15.

While I have disclosed one embodiment of the present invention, it is tobe understood that this embodiment is given by way of example only andnot in a limiting sense, the scope of the present invention beingdetermined by the objects and the claims.

I claim:

1. An electric hand riveting device, comprising an electric motor,

a reduced gear operatively connected with said electric motor,

a gear wheel having a gap without teeth and being operatively connectedwith said reduction gear,

a connecting rod having one end pivotally and eccentrically connectedwith said gear wheel, and

said gap causing the automatic standstill of said connecting rod.

2. The electric hand riveting device, as set forth in claim 1, whichincludes a pulling lever,

a slide means receiving one end of said pulling lever for being slid bythe latter,

a grooved cam secured to said gear wheel,

a pin projecting from said slide into said grooved cam,

and

said gear wheel being retained in the standstill position by means ofsaid pulling lever and said pin on said slide and by cooperation withsaid grooved cam.

3. The electric hand riveting machine, as set forth in claim 2, whereinsaid grooved cam has a first set-01f abutment which cooperates with saidpin to free said gear Wheel, upon pulling said pulling lever and saidconnecting rod being adapted to free the mechanism of a rivet head forthe clamping of a blind rivet.

4. The electric hand riveting machine, as set forth in claim 3, whereinsaid grooved cam has a second set-off abutment, which cooperates withsaid pin and upon pulling said pulling lever beyond to said secondabutment, said electric motor is switched on, and which includes apinion operatively disposed between said reduction gear and said gearwheel and meshing the latter,

said pinion engaging the teeth of said wheel gear and said pulling leveris maintained in engaging position by said grooved cam with said slideuntil the riveting cycle is completed after one revolution of said wheelgear, and thereby frees said switch which shuts off said electric motor.

5. An electric hand riveting device, comprising a housing,

an electric motor mounted in said housing,

a gear wheel having teeth and a gap without teeth and operativelyconnected with said electric motor for turning until said gap isadjacent said operative connection to said electric motor, and

a connecting rod mounted at one end for reciprocating movement in saidhousing and connected pivotally at the other end eccentrically with saidgear wheel.

6. The electric hand riveting device, as set forth in claim 5, furthercomprising,

means for urging said gear wheel to rotate when said gap is adjacentsaid operative connection to said electric motor so that said teethoperatively engages therewith,

switching means for preventing rotation of said gear wheel when said gapis positioned adjacent said operative connection to said electric motor,and

said switching means further for being actuated to free said gear wheelfor rotation.

7. The electric hand riveting device, as set forth in claim 6, whereinsaid means for urging said gear'wheel to rotate comprises a springeccentrically secured operatively to said gear wheel and to saidhousing.

8. The electric hand riveting device, as set forth in claim 6, whereinsaid switching means comprises,

an abutment operatively secured to said gear wheel,

a pin means cooperating with said abutment for preventing rotation ofsaid gear wheel,

said pin means for automatically cooperating with said abutment whensaid gap is rotated into position adjacent said operative connection tosaid electric motor, and

means for moving said pin means out of cooperation with said abutment.

9. The electric hand riveting device, as set forth in claim 8, whereinsaid abutment comprises a first surface substantially facing in thedirection of rotation of said gear wheel.

10. The electric hand riveting device, as set forth in claim 9, whereinSaid switching means further comprises,

a cam groove including said abutment and continuous and eccentricallyoriented from an inner radial end of said first surface to an outerradial end of said first surface,

said means for moving said pin means out of cooperation with saidabutment including a slide secured to said pin means for sliding saidpin means beyond said first surface to said cam groove, thereby causingsaid means for urging said gear wheel to rotate, to rotate said gearwheel and causing said electric motor to further turn said gear wheelwhen operative engagement therewith occurs, and

said pin means thereby sliding along said cam groove until reaching saidfirst surface again.

11. The electric hand riveting device, as set forth in claim 10, furthercomprising a second abutment surface spaced from said first surface,

said cam groove including a portion arcuately connecting said first andsecond abutment surfaces,

said pin means sliding from said first surface to said second abutmentsurface along said portion when said slide moves said pin means beyondsaid first surface causing said means for urging said gear wheel torotate, to rotate said gear wheel,

said pin means automatically cooperating with said second abutmentsurface when said pin means reaches said second surface for preventingfurther rotation of said gear wheel,

said second abutment surface substantially faces in the direction ofrotation of said gear wheel,

said cam groove including said second abutment surface and eccentricallyoriented from one end of said second abutment surface to said firstabutment surface,

said means for moving said pin means out of cooperation with saidabutment further adapted to slide said pin means beyond said secondabutment surface, thereby freeing said gear wheel for rotation, and

said second abutment surface spaced from said first abutment surface adistance cooperative with said gap and sufiicient for one of said teethof said gear wheel to engage said operative connection to said electricmotor when said pin means reaches said second surface.

12. The electric hand riveting device, as set forth in claim 11, furthercomprising a switch means for said electric motor, and

said means for moving said pin means includes a means for actuating saidswitch means when said pin means is moved beyond said second abutmentsurface and for turning off said switch means to stop said electricmotor when said pin means reaches said first surface.

13. The electric hand riveting device, as set forth in claim 10, whereinsaid means for moving said pin means out of cooperation with saidabutment further includes,

a double-armed pulling lever pivotally secured to said housing for beingpivoted at one arm thereof and having its other arm connected to saidslide for sliding said slide when being pivoted.

14. The electric hand riveting device, as set forth in claim 13, furthercomprising a switch means for said electric motor disposed adjacent andin the path of pivoting of said one arm and adapted to be actuated toturn on said electric motor when said pulling lever is pivoted and toturn off said motor when said lever returns to an inoperative position,and

said eccentric cam groove returning said lever via said pin means andslide to its inoperative position when said pin means reaches said firstabutment surface, thereby turning off said electric motor when said gapbecomes positioned adjacent said operative connection to said motor.

References Cited UNITED STATES PATENTS 2,075,162 3/1937 Begg 227-1312,283,665 5/1942 Cadden 72-391 2,965,258 12/ 1960 Wilson et al 72391 X3,074,343 1/ 1963 McDufl'le 74-435 X CHARLES E. OCONNELL, PrimaryExaminer.

DAVID H. BROWN, FRED C. MATTERN, Examiners.

L. P. KESSLER, Assistant Examiner.

